Diagnostic Instructions
DTC Descriptor
DTC 024: PPS Ignition 1 Voltage Performance
Circuit/System Description
The inflatable restraint passenger presence system (PPS) is used to monitor the weight of an occupant on the front outboard passenger seat and communicate the status to the sensing and diagnostic module (SDM) whether to enable or suppress the deployment
of the instrument panel (I/P) module. The PPS consist of an electronic control module, silicone filled sensor pad, pressure sensor, seat belt tension retractor sensor, wiring harness, and PASSENGER AIR BAG ON/OFF indicators. The silicone filled sensor pad is
located under the passenger seat foam cushion and is connected by a hose clamped to the pressure sensor. The weight of the occupant sitting in the front passenger seat is measured as a pressure change within the bladder by the pressure sensor. The pressure sensor
sends a voltage signal to the PPS module. If the pressure from the occupant's weight is less than a specified value, the PPS module will send a suppress signal to the SDM to disable the I/P module. If the pressure from the occupants weight is higher than a specified
value, the PPS module will send an enable signal to the SDM to enable the I/P module. The PPS module will notify the customer of the enable/disable status by turning on one of the PASSENGER AIR BAG ON/OFF indicators located on the instrument panel. The PPS monitors
itself for faults and will set flash DTCs if a fault is detected. The PPS will also notify the SDM of a fault. The SDM will respond by setting either DTC B0092 or B0098 and requesting the instrument panel cluster (IPC) to turn the AIR BAG indicator ON.
Conditions for Running the DTC
Ignition 1 voltage is within the normal operating voltage range.
Conditions for Setting the DTC
The PPS detects ignition 1 voltage is less than 8 volts for 500 milliseconds.
Action Taken When the DTC Sets
| • | The SDM disables the instrument panel (I/P) module deployment loop. |
| • | The SDM commands the AIR BAG indicator ON via class 2 serial data. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | The scan tool CLEAR DTC command has been issued. |
| • | A history DTC will clear once 255 malfunction-free ignition cycles have occurred. |
Diagnostic Aids
The following can cause an intermittent condition:
| • | A short in the ignition 1 voltage circuit between the PPS module and the body relay block |
| • | An open or high resistance in the ignition 1 voltage circuit between the PPS module and the body relay block |
The PPS will set DTC 024 when the ignition voltage has fallen below 8 volts. The PPS will set DTC 024 as a history code only. This is a normal condition for DTC 024 and it should be diagnosed as a current DTC.
Reference Information
Schematic Reference
SIR Schematics
Connector End View Reference
SIR Connector End Views
Electrical Information Reference
Circuit/System Testing
- Ignition OFF. Inspect the PPS and main seat harness connectors for corrosion or damage.
| ⇒ | If any of the above conditions are found, make the appropriate repair. |
- Test the PPS ground circuit for an open/high resistance.
| ⇒ | If any of the above conditions are found, make the appropriate repair. |
- Test the PPS ignition 1 voltage circuit for a short to ground or an open/high resistance.
| ⇒ | If any of the above conditions are found, make the appropriate repair. |
- Reconnect all components, clear codes and recheck for DTC 024. Refer to
Passenger Presence System Flash Code Procedures
. If DTC 024 resets, replace and rezero the PPS.
| ⇒ | After replacement and rezeroing of the PPS are completed, perform the repair verification. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
